Problem sending the command to the program

I have perused the web and not found a ready answer to this problem, although it has apparently been out there for several years. I am running Win 7 X64 and first had this problem using Firefox. Then I set IE as default browser, and it is now happening with IE. More and more programs are not opening, or links in Outlook that try to open something in IE ... I get the error message and a blank IE screen. In Firefox, I'd get the message and then the window would open ... irritating but better than no window opening at all. What is the fix? One source I pulled up mentioned changing a registry key, but didn't tell me how/where to find instructions. I am open to suggestions ... this is frustrating. Thanks.
Nancy

I changed Firefox to the default browser and got the error message immediately. It seems to be less consistent with IE, but getting more frequent. I did run Spyware/Malware stuff when this started to happen with Firefox a month or two ago, but didn't find anything and the problem continued. I switched to IE out of frustration and because someone hinted it might be a conflict just with FF, but apparently not ... There are many references to this on the web, but few solutions that I have found. Thanks for your prompt reply and your assistance!
Nancy

I opened my Windows Mobile program this AM to synch my phone, and clicked on the help button, and got the same error ... actually, for awhile nothing opened but an empty window, and then I got the error. That was on IE. Is that because the synch is connected to Outlook? I do recall that when I found references to this problem on the web, it was around Access or Excel, so it most certainly could be an Office 07 issue.
Nancy

My question is, is the problem occurring when I am not directly opening Outlook, but instead trying to open the HELP program in Windows Mobile, because the mobile app uses Outlook? Because otherwise, the problem is occurring in OTHER applications besides just Outlook.
Nancy